1. Field of the Disclosure
The present disclosure relates generally to a system for transfer of charged toner particles in an electrostatographic printing apparatus, and more particularly, concerns a non-contact limited ozone producing transfer device used in such a machine.
2. Description of Related Art
Typically, in an electrostatographic printing process of printers, such as, U.S. Pat. No. 6,033,452, which is incorporated herein by reference to the extent necessary to practice the present disclosure, a photoconductive member is charged to a substantially uniform potential so as to sensitize the surface thereof. The charged portion of the photoconductive member is exposed to selectively dissipate the charges thereon in the irradiated areas. This records an electrostatic latent image on the photoconductive member. After the electrostatic latent image is recorded on the photoconductive member, the latent image is developed by bringing a developer material into contact therewith. Generally, the developer material comprises toner particles adhering triboelectrically to carrier granules. The toner particles are attracted from the carrier granules either to a donor roll or to a latent image on the photoconductive member. The toner attracted to the donor roll is then deposited on latent electrostatic images on a charge retentive surface, which is usually a photoreceptor. The toner powder image is then transferred from the photoconductive member to a copy substrate.
In order to fix or fuse the toner material onto a support member permanently by heat, it is necessary to elevate the temperature of the toner material to a point at which constituents of the toner material coalesce and become tacky. This action causes the toner to flow, to some extent, onto fibers or pores of the support members or otherwise upon surfaces thereof. Thereafter, as the toner materials cool, solidification of the toner materials occurs causing the toner material to be bonded firmly to the support member.
Transfer is typically carried out by the creation of a “transfer-detack zone” (often abbreviated to just “transfer zone”) of AC and DC biases where the print sheet is in contact with, or otherwise proximate to, the photoconductive member. A DC bias applied to the back (i.e., on the face away from the photoconductive member) of the paper or other substrate in the transfer zone electrostatically transfers the toner from the photoconductive member to the paper or other substrate presented to the transfer zone. The toner particles are heated to permanently affix the powder image to the copy substrate. Biased transfer rolls are also used to transfer an image from a photoconductive member to media, for example, the segmented bias roll disclosed in U.S. Pat. No. 3,847,478.
These traditional image transfers are done using charging devices which produce ozone and apply pressure directly to a transfer media to remove the image from a photoconductive member. Removal of this ozone has traditionally been done utilizing extensive air handling systems that add additional cost into the printer.
Thus, there is a need for a transfer device that: reduces the amount of air systems needed to remove ozone; eliminates the transfer system media pressure contact; and reduces the degradation of components in the transfer systems.